Houston mayoral challenger Tony Buzbee followed through his pledge to sue Mayor Sylvester Turner Wednesday, claiming that donated billboards for the city's AlertHouston! campaign violate campaign finance laws because they feature a photo of Turner.

The lawsuit, filed in the 281st state district court, names Turner and Clear Channel Outdoor Inc., the company that donated the 27 billboards, as defendants.

Buzbee's petition claims Clear Channel is "blatantly supporting" Turner in the November mayoral race "by plastering his smiling face across this city while promoting him as a civic-minded, safety conscious leader."

The billboards promote AlertHouston!, a system that sends alerts to Houston residents during emergency situations.

Turner spokeswoman Mary Benton said the city's Office of Emergency Management chose Turner to be the spokesperson for AlertHouston!'s promotional campaign because the mayor acts as the city's emergency manager during natural disasters and emergencies.

"It is unfortunate that some would choose to politicize this very important public safety message," Benton said. "However, the administration welcomes the media attention given to the AlertHouston campaign, in hopes that it may actually help to save lives."

In the petition, Buzbee wrote that Clear Channel's vice president for public affairs, Lee Vela, "works closely with Turner, and routinely convinces him to allow the relocation of billboards that would otherwise be eliminated" through a city policy that limits the number of billboards in Houston.

Buzbee further alleged that the company "needs the mayor's help" to allow digital billboards in the city, which Buzbee said Clear Channel has pushed hard for recently.

A Clear Channel spokesperson did not respond to a request for comment Wednesday.

Buzbee is seeking damages worth twice the value of the billboards, a remedy laid out in a section of Texas' Election Code dealing with civil liability. He estimated the billboards are worth $216,000 per month.

Buzbee also said he would dismiss the suit if Turner and Clear Channel issue a public apology and remove Turner's photo from each billboard.

"Half of the billboard is the mayor's face, smiling. If they really wanted to draw attention to folks to look at this billboard, then maybe they should have used somebody like (Astros player Jose) Altuve or Beyonce," said Chad Pinkerton, Buzbee's attorney.

Pinkerton also said the portion of the billboard featuring Turner takes up much more space than the part mentioning AlertHouston!

In addition to filing the suit, Buzbee has asked Attorney General Ken Paxton to intervene, writing that the state "has the absolute authority to take action."

Jasper covers City Hall, local politics and breaking news for the Houston Chronicle through the Hearst Journalism Fellowship program. He previously covered Bexar County and local politics for the San Antonio Express-News. Jasper graduated from Northwestern University in 2017 with degrees in journalism and political science. He has interned for the Tampa Bay Times, Washington Post and Fortune magazine.